Currently, io_buffer_register_bvec() takes in a request. In preparation for supporting kernel-populated buffers in fuse io-uring (which will need to register bvecs directly, not through a struct request), rename this to io_buffer_register_request(). A subsequent patch will commandeer the "io_buffer_register_bvec()" function name to support registering bvecs directly. Rename io_buffer_unregister_bvec() to a more generic name, io_buffer_unregister(), as both io_buffer_register_request() and io_buffer_register_bvec() callers will use it for unregistration. Signed-off-by: Joanne Koong Reviewed-by: Caleb Sander Mateos --- Documentation/block/ublk.rst | 14 +++++++------- drivers/block/ublk_drv.c | 22 +++++++++++----------- include/linux/io_uring/cmd.h | 26 ++++++++++++++++++++------ io_uring/rsrc.c | 14 +++++++------- 4 files changed, 45 insertions(+), 31 deletions(-) diff --git a/Documentation/block/ublk.rst b/Documentation/block/ublk.rst index 6ad28039663d..f014d1d69019 100644 --- a/Documentation/block/ublk.rst +++ b/Documentation/block/ublk.rst @@ -382,17 +382,17 @@ Zero copy --------- ublk zero copy relies on io_uring's fixed kernel buffer, which provides -two APIs: `io_buffer_register_bvec()` and `io_buffer_unregister_bvec`. +two APIs: `io_buffer_register_request()` and `io_buffer_unregister`. ublk adds IO command of `UBLK_IO_REGISTER_IO_BUF` to call -`io_buffer_register_bvec()` for ublk server to register client request +`io_buffer_register_request()` for ublk server to register client request buffer into io_uring buffer table, then ublk server can submit io_uring IOs with the registered buffer index. IO command of `UBLK_IO_UNREGISTER_IO_BUF` -calls `io_buffer_unregister_bvec()` to unregister the buffer, which is -guaranteed to be live between calling `io_buffer_register_bvec()` and -`io_buffer_unregister_bvec()`. Any io_uring operation which supports this -kind of kernel buffer will grab one reference of the buffer until the -operation is completed. +calls `io_buffer_unregister()` to unregister the buffer, which is guaranteed +to be live between calling `io_buffer_register_request()` and +`io_buffer_unregister()`. Any io_uring operation which supports this kind of +kernel buffer will grab one reference of the buffer until the operation is +completed. ublk server implementing zero copy or user copy has to be CAP_SYS_ADMIN and be trusted, because it is ublk server's responsibility to make sure IO buffer diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c index 004f367243b6..b9f293261240 100644 --- a/drivers/block/ublk_drv.c +++ b/drivers/block/ublk_drv.c @@ -1627,8 +1627,8 @@ ublk_auto_buf_register(const struct ublk_queue *ubq, struct request *req, { int ret; - ret = io_buffer_register_bvec(cmd, req, ublk_io_release, - io->buf.auto_reg.index, issue_flags); + ret = io_buffer_register_request(cmd, req, ublk_io_release, + io->buf.auto_reg.index, issue_flags); if (ret) { if (io->buf.auto_reg.flags & UBLK_AUTO_BUF_REG_FALLBACK) { ublk_auto_buf_reg_fallback(ubq, req->tag); @@ -1868,7 +1868,7 @@ static int __ublk_batch_dispatch(struct ublk_queue *ubq, ublk_io_unlock(io); if (index != -1) - io_buffer_unregister_bvec(data->cmd, index, + io_buffer_unregister(data->cmd, index, data->issue_flags); } @@ -3091,8 +3091,8 @@ static int ublk_register_io_buf(struct io_uring_cmd *cmd, if (!req) return -EINVAL; - ret = io_buffer_register_bvec(cmd, req, ublk_io_release, index, - issue_flags); + ret = io_buffer_register_request(cmd, req, ublk_io_release, index, + issue_flags); if (ret) { ublk_put_req_ref(io, req); return ret; @@ -3123,8 +3123,8 @@ ublk_daemon_register_io_buf(struct io_uring_cmd *cmd, if (!ublk_dev_support_zero_copy(ub) || !ublk_rq_has_data(req)) return -EINVAL; - ret = io_buffer_register_bvec(cmd, req, ublk_io_release, index, - issue_flags); + ret = io_buffer_register_request(cmd, req, ublk_io_release, index, + issue_flags); if (ret) return ret; @@ -3139,7 +3139,7 @@ static int ublk_unregister_io_buf(struct io_uring_cmd *cmd, if (!(ub->dev_info.flags & UBLK_F_SUPPORT_ZERO_COPY)) return -EINVAL; - return io_buffer_unregister_bvec(cmd, index, issue_flags); + return io_buffer_unregister(cmd, index, issue_flags); } static int ublk_check_fetch_buf(const struct ublk_device *ub, __u64 buf_addr) @@ -3280,7 +3280,7 @@ static int ublk_ch_uring_cmd_local(struct io_uring_cmd *cmd, goto out; /* - * io_buffer_unregister_bvec() doesn't access the ubq or io, + * io_buffer_unregister() doesn't access the ubq or io, * so no need to validate the q_id, tag, or task */ if (_IOC_NR(cmd_op) == UBLK_IO_UNREGISTER_IO_BUF) @@ -3347,7 +3347,7 @@ static int ublk_ch_uring_cmd_local(struct io_uring_cmd *cmd, req = ublk_fill_io_cmd(io, cmd); ret = ublk_config_io_buf(ub, io, cmd, addr, &buf_idx); if (buf_idx != UBLK_INVALID_BUF_IDX) - io_buffer_unregister_bvec(cmd, buf_idx, issue_flags); + io_buffer_unregister(cmd, buf_idx, issue_flags); compl = ublk_need_complete_req(ub, io); if (req_op(req) == REQ_OP_ZONE_APPEND) @@ -3682,7 +3682,7 @@ static int ublk_batch_commit_io(struct ublk_queue *ubq, } if (buf_idx != UBLK_INVALID_BUF_IDX) - io_buffer_unregister_bvec(data->cmd, buf_idx, data->issue_flags); + io_buffer_unregister(data->cmd, buf_idx, data->issue_flags); if (req_op(req) == REQ_OP_ZONE_APPEND) req->__sector = ublk_batch_zone_lba(uc, elem); if (compl) diff --git a/include/linux/io_uring/cmd.h b/include/linux/io_uring/cmd.h index 89e1a80d9f5f..165d436073a4 100644 --- a/include/linux/io_uring/cmd.h +++ b/include/linux/io_uring/cmd.h @@ -106,6 +106,12 @@ bool io_uring_is_kmbuf_ring(struct io_uring_cmd *cmd, unsigned int buf_group, struct io_br_sel io_ring_buffer_select(struct io_kiocb *req, size_t *len, struct io_buffer_list *bl, unsigned int issue_flags); + +int io_buffer_register_request(struct io_uring_cmd *cmd, struct request *rq, + void (*release)(void *), unsigned int index, + unsigned int issue_flags); +int io_buffer_unregister(struct io_uring_cmd *cmd, unsigned int index, + unsigned int issue_flags); #else static inline int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, @@ -184,6 +190,20 @@ static inline struct io_br_sel io_ring_buffer_select(struct io_kiocb *req, }; return sel; } +static inline int io_buffer_register_request(struct io_uring_cmd *cmd, + struct request *rq, + void (*release)(void *), + unsigned int index, + unsigned int issue_flags) +{ + return -EOPNOTSUPP; +} +static inline int io_buffer_unregister(struct io_uring_cmd *cmd, + unsigned int index, + unsigned int issue_flags) +{ + return -EOPNOTSUPP; +} #endif static inline struct io_uring_cmd *io_uring_cmd_from_tw(struct io_tw_req tw_req) @@ -233,10 +253,4 @@ static inline void io_uring_cmd_done32(struct io_uring_cmd *ioucmd, s32 ret, return __io_uring_cmd_done(ioucmd, ret, res2, issue_flags, true); } -int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq, - void (*release)(void *), unsigned int index, - unsigned int issue_flags); -int io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index, - unsigned int issue_flags); - #endif /* _LINUX_IO_URING_CMD_H */ diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c index 52554ed89b11..7579f6992a25 100644 --- a/io_uring/rsrc.c +++ b/io_uring/rsrc.c @@ -924,9 +924,9 @@ int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, return ret; } -int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq, - void (*release)(void *), unsigned int index, - unsigned int issue_flags) +int io_buffer_register_request(struct io_uring_cmd *cmd, struct request *rq, + void (*release)(void *), unsigned int index, + unsigned int issue_flags) { struct io_ring_ctx *ctx = cmd_to_io_kiocb(cmd)->ctx; struct io_rsrc_data *data = &ctx->buf_table; @@ -986,10 +986,10 @@ int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq, io_ring_submit_unlock(ctx, issue_flags); return ret; } -EXPORT_SYMBOL_GPL(io_buffer_register_bvec); +EXPORT_SYMBOL_GPL(io_buffer_register_request); -int io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index, - unsigned int issue_flags) +int io_buffer_unregister(struct io_uring_cmd *cmd, unsigned int index, + unsigned int issue_flags) { struct io_ring_ctx *ctx = cmd_to_io_kiocb(cmd)->ctx; struct io_rsrc_data *data = &ctx->buf_table; @@ -1019,7 +1019,7 @@ int io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index, io_ring_submit_unlock(ctx, issue_flags); return ret; } -EXPORT_SYMBOL_GPL(io_buffer_unregister_bvec); +EXPORT_SYMBOL_GPL(io_buffer_unregister); static int validate_fixed_range(u64 buf_addr, size_t len, const struct io_mapped_ubuf *imu) -- 2.52.0